Strip away the noise and mining profitability comes down to four numbers. Learn to read them and you can evaluate any machine, any facility, any offer in minutes.
Hashprice expresses miner revenue in dollars per terahash per day — collapsing BTC price, network difficulty, block subsidy and fees into a single market number. When hashprice is $0.05/TH/day, a 200 TH machine grosses about $10 daily, full stop. Track it over time and you see mining's entire economic weather; indexes publish it live. Every revenue projection you build should start here, not from a coin-price guess.
J/TH measures how much energy a machine spends per unit of work — the spec that decides who survives difficulty growth and halvings. The arithmetic: watts ÷ TH/s. An S21 Pro at 3,510 W / 234 TH = 15 J/TH; an aging S19j Pro sits near 30. At identical power prices the efficient machine's margin is dramatically wider, and in a falling-hashprice environment the inefficient one hits zero first. When comparing purchase offers, dollars-per-terahash means nothing without J/TH beside it.
Your true power cost is the hosting rate plus everything hiding around it — fees, curtailment sharing, minimums. Daily profit = (hashrate × hashprice) − (kW × 24 × all-in rate). Breakeven months = total hardware investment ÷ monthly profit. Run it under three difficulty scenarios, not one. A machine that breaks even in 14 months flat-difficulty but 26 months under realistic growth is a 26-month decision.
Our free calculators pull live BTC price and network difficulty so the four numbers above are computed from reality rather than promotional assumptions — profitability, hosting cost, ROI and share sizing in one place. Whatever you do with the result, insist on this standard everywhere: any mining offer that won't show its hashprice, efficiency and all-in power assumptions isn't an offer, it's a brochure.